componentWillReceiveProps(nextProps: any) {
   this.setState({
     dataSource: nextProps.messages ? ds.cloneWithRows(nextProps.messages) : ds.cloneWithRows([])
   });
 }
 constructor(props: any) {
   super(props);
   this.state = {
     dataSource: props.messages ? ds.cloneWithRows(props.messages) : ds.cloneWithRows([])
   };
 }